Type Method

dataWithContentsOfURL:options:error:

Creates a data object containing the data from the location specified by a given URL.

Declaration

+ (instancetype)dataWithContentsOfURL:(NSURL *)url options:(NSDataReadingOptions)readOptionsMask error:(NSError * _Nullable *)errorPtr;

Parameters

aURL

The URL from which to read data.

mask

A mask that specifies options for reading the data. Constant components are described in NSDataReadingOptions.

errorPtr

If there is an error reading in the data, upon return contains an error object that describes the problem.

Discussion

Use this method to convert data:// URLs to NSData objects. You can also use it to read short files synchronously. If you need to read potentially large files, use inputStreamWithURL: to open a stream, then read the file incrementally.

This method may fail and return nil for various reasons, like bad URLs and file-not-found errors. In this case, the reason for error is indicated by errorPtr.

See Also

Reading Data from a File

dataWithContentsOfFile:

Creates a data object by reading every byte from the file at a given path.

dataWithContentsOfFile:options:error:

Creates a data object by reading every byte from the file at a given path.

dataWithContentsOfURL:

Creates a data object containing the data from the location specified by a given URL.

initWithContentsOfFile:

Initializes a data object with the content of the file at a given path.

initWithContentsOfFile:options:error:

Initializes a data object with the content of the file at a given path.

initWithContentsOfURL:

Initializes a data object with the data from the location specified by a given URL.

initWithContentsOfURL:options:error:

Initializes a data object with the data from the location specified by a given URL.

NSDataReadingOptions

Options for methods used to read data objects.

initWithContentsOfMappedFile:

Initializes a data object with the contents of the mapped file specified by a given path.

Deprecated
dataWithContentsOfMappedFile:

Creates a data object from the mapped file at a given path.

Deprecated